Apparatus for cross folding flexible sheets



Jan. 14, 1964 R. FUNK 3,117,777

APPARATUS FOR CROSS FOLDING FLEXIBLE SHEETS Filed March 13, 1962 2 Sheets-Sheet 1 9&4 BY RUDOLPH Fume ATTORNEY Jan. 14, 1964 R. FUNK 3,117,777

APPARATUS FOR CROSS FOLDING FLEXIBLE SHEETS Filed March 15. 1962 2 Sheets-Sheet 2 INVENTOR. RUDOLPH FUNK ATTO RNEY United States Patent 0 3,117,777 APPARATUS CRQSS FQLDHNG SHEETS Rudolph Funk, .lamison, Pa. (R. Funk dz tie. inn, N. Eastern Road, Doylestovvn, Pa.)

13, 39132, Ser. No. 179,387 5 flat-ms. {$1. 270-31) This invention relates to apparatus for cross folding flexible sheets.

in my US. application Serial No. 775,427, filed Nov. 21, 1958, entitled Apparatus for Folding Flexible Sheets, now issued as Patent No. 3,052,464, dated September 4, 1962, l disclosed a complete system for folding a sheet in accordion folds and delivering a rudimentary packet comprised of the panels defined by the accordion folds, to a tray or the like, and thereafter securing relative movement of the rudimentary packet and cross-folding mechanism until suitable juxtaposition was established, the cross folding the rudimentary packet into a packet or a semi-packet. As a refinement the sheets delivered to the apparatus in random order of lengths and widths were divided into sheets of minor width and sheets of major widths, and the cross-folding means was organized to make a single cross-fold in rudimentary packets formed of sheets of minor width, and two successive cross-folds in rudimentary packets formed from sheets of major widths, forming packets of the same lateral dimensions from sheets of both minor and major widths, and in which the selection of one or two cross folds was an automatic function of the width of an instant sheet.

The apparatus of said application has attained excellent commercial acceptance, is of high eiliciency and utility and fills a long felt need. However the apparatus is relatively expensive, has some tirne delays, and because of minimal control of one end of the accordion folded and once cross folded semipacket in the second fold mechanism, may occasionally cause damage to the sheet.

Among the objects of the present invention are; to improve the cross-folding of sheets; to reduce the time between accordion-folding and cross-folding; to minimize the shock to the apparatus incident previously to crossfolding an accordion-folded sheet; to improve the actuation and control of a cross-folding blade; to conbine with a cross-folding blade a movable guide for compressing and guiding a cross folded sheet; to insure in cross folding accordion-folded sheets, that the portion of the accordion folded rudimentary semi-packet extending beyond the minimum major width is positively guided into the cross folding mechanism; to provide folding mechanism whereby improved accuracy of folding is assured; to provide a creasing blade in cocked angular relation to a rudimentary packet during the formation of the latter, and by a single cam to effect a compound motion of the creasing blade in which it first moves into parallelism with the rudimentary packet then moves toward and against said packet; to provide in combination in a second cross folding mechanism for semi-packets a creasing blade and a guiding movable member with op erating means whereby the blade and movable guiding member are both retracted to permit the passage of the semi-packet, the blade and guiding means move in synchronism against the semi-packet to crease same and guide it into crease rolls, and wherein the blade is quickly retracted thereafter whereas the movable guide means remains in guiding contact with the continuous portion of the semi-packet until it has been completely drawn into the crease rolls; and many other objects and advantages that will become apparent as the description procoeds.

In the accompanying drawings forming part of this description:

iii)

till??? FlG. 1 represents a fragmentary schematic side elevation of sheet folding apparatus according to the invention, with a creasing blade thereof in its lowermost attitude, parallel to the axes of, and partially between horizontal crease rolls, and with the two res ective studs or rollers of the lever mounting the blade, both disposed and lowered in the linear portion or" the guide groove in the frame.

FIG. 2 represents a fragmentary schematic side elevation of the creasing blade, on a slightly enlarged scale, in its attitude of maximum retraction, or cocking, relative to a rudimentary packet (not shown) in which one stud or roller of the blade mounting lever, forming its fulcrum, is disposed in the linear portion of the guide groove, and the other stud or roller thereof is in the curved extension of the guide groove.

FIG. 3 represents a View similar to that of FIG. 2, with the blade in parallel relation to and above a rudimentary packet disposed on crease rolls, in a secondary attitude of the blade and its mounting lever, in which the lever-mounted studs or rollers are in alignment in the linear portion of the guide groove, preliminary to moving to the third, creasing position shown in FIG. 1.

FIG. 4 represents a fragmentary front elevation of the apparatus as shown in FIG. 1, showing the relation of the blade to the rudimentary packet and to the crease rolls and showing the illustrative cam by which the compound blade operation is secured.

FIG. 5 represents a fragmentary schematic elevation of the second cross folding portion of the apparatus, with a modified form of blade and blade mounting, with the pivotally movable trap door guide m mber and blade both retracted, and with a semi-packet, having an exposed free end to be controlled by the movable guiding element, partially disposed between the movable and fixed guiding elements, and showing the instantaneous cam position or attitude consonant with the disposition of the parts.

FIG. 6 represents the attitude of the parts in FIG. 5 as the blade has been moved inwardly in response to cam actuation to its maximum creasing extent engaging the semi-packet, and the pivotally movable guide has moved into substantially uninterrupted coextensive alignment with the fixed guide on which it is mounted and into engagement or substantial engagement with the portion of the semi-packet below the blade, to guide the latter portion into the crease rolls as the latter draw the said portion upwardly, consonant with maximum extension of the blade and movable guide by the cam.

FIG. 7 represents the attitude of the parts immediately following the blade actuation creasing the semi-packet and introducing it between the crease rolls, in which the cam has turned far enough to permit the blade to move bacl; partially so as to be out of its creasing position, while still holding the movable guide element in position to complete the guidance of the semi-packet, with a just second folded packet shown for illustration as being discharged from the crease rolls.

For illustrative purposes it will be understood that the basic sheets to be folded may be presented in random order and may be of widely disparate lengths and widths. These respectively are presented to accordion folding apparatus A (FIGURE 1), of any desired sort, and, for illustrative purposes comprises the accordion folding mechanism of said application. The varying lengths are taken care of by continuing accordion folding. Let it be assumed, again for illustrative purposes, that any given sheet is accordion folded into three panels, comprising a first panel ll, a second panel 16} and a terminal panel 12,. When so folded the sheet forms a rudimentary packet 7, with the panels in general parallelism so that the rudimentary packet 7 is relatively planar. This is deposited 3 on a tray 8, containing at least crease rolls 15 and 16 (with their axes parallel to the tray), and, additional pairs of crease rolls (not shown) in spaced relation to crease rolls l and 16.

It being recognized that the widths of the sheets, within the capacity of the apparatus, may have widely disparate dimensions, and it being intended that the ultimate packets formed by the folded sheets have the same lateral dimensions, regardless of the lengths or Widths of the instant respectively discrete sheets, the sheets are coordinated with the apparatus in two width groups. For illustrative purposes these are considered as minor widths and major widths. If it be assumed that the ultimate packet is to have one dimension of 8 /2" (with the other dimension predetermined by the width of the panels comprising the rudimentary packet), it wil be seen that a sheet width of between 8 /2" and 17" comprises a minor width, having a maximum width dimension of 17, and a sheet of a width between 17" and 34" comprises a sheet of major width. In order to establish the same ultimate lateral dimension of the packet it is necessary to establish a first cross fold in sheets of minor width, 8 /2" from an edge, regardless of the remaining width distance between 8 /2 and 17". Relatedly, with sheets of major width, it is necessary to form a first cross fold 1 from said edge, and then to form a second cross fold 8 /2 from said edge to establish said given lateral dimensions. It will be clear that in this latter case the folding of the rudimentary sheet into the semi-packet Will be at such location as will establish on one side a dimension of 17'', whereas on the other side there will be established an area comprising a free edge or fold varying between '17" and almost zero. It is this last mentioned free edge or fold 29, attached to the semi-packet only at the fold, which may be considered as a raw or free floating edge, which causes he difiicu-lty in the formation or the second cross fold, which this invention obviates. If the width of the semi-packet is greater than the maximum minor Width (the illustrative 17") but less than one and one half maximum minor widths, the free end 29 of the semi-packet is exposed in an unfortunate attitude for entry between the second pair of crease rolls, to be described, and this is true of all lengths of free ends of sheets of major widths, and especially of very short free ends because of the bias on such ends incident to the first cross folding. It is a fundamental object of this invention to positively guide such ends into and between such crease rolls to preclude damage to the sheet.

Let it be assumed that a given sheet has been accordion folded by such means as A, in FIG. 1, to establish on tray 8 (P16. 3), a first panel 11, a second panel 1 3, and a terminal panel 12, in a rudimentary packet 7. Let it be assumed further, as shown in FIG. 7, that this rudimentary packet 7 has been deposited as a generally planar member 7 on tray 8 with the latter containing crease rolls and 16, for sheets of major widths, and additional spaced, parallel like-rolls, for sheets of minor widths (not shown). A creasing blade 59 (as further explained in connection with FIGS. 1-4), forces a crease into the rudimentary packet 7, forcing the convergent surfaces thereof into the crease rolls l5 and 16, which, for purposes of illustration, are normally downwardly delivering, forming a semi-packet 14, so that with a leading edge crease or fold =17, the semi-packet 14- is directed downwardly between generally vertical guide plates 9- 19, toward and delivering the single cross-folded accordion-folded, or other sheet (a semi-packet), as shown in FIG. 5, to generally horizontally aligned horizontal feed rolls 18 and 2% The semi-packet 14 is delivered beside and tangentially of horizontal, generally vertically aligned, creasing rollers, respectively 18 and 22, on a vertical path established by vertical guide plates 9 and 1&9 and generally horizontally aligned feeding rollers 18 and 2:3. in this connection rollers 22 and 2% are free floating, but suitably 1 spring biased transversely of their axes, as to account for various thicknesses of semi-packets 14, as shown in said application. 7 p

Upon a framework or support 23 the said stationary generally parallel guide plates 9 and 19 direct the semipacket 14 to the feeding rolls and 29, which latter propel the semi-packet 14 downwardly along a predetermined path, one side of which is defined by the stationary upwardly curved guide plate 24, mounted on frame 23. The upwardly curved end of guide plate 24 partially overlies crease roll 22, out of contact therewith in the upward biased position of the latter.

At its lower end guide plate 24 has parallel spaced relation to removable but relatively stationary guide plate 25, defining with plate 24 a semi-packet-receiving slot, or gap, 27. It wi l be noted that the upper curved end 25 of the guide plate 24 extends across and generally intecepts the path of the leading edge 17 of the cross folded semi-packet 14, so as to easily direct the downwardly fed semi-packet 1d into slot 27 and preventing damaging impingement against roll 22.

On a horizontal pivot 39, adjacent the upper linear edge of stationary slot-defining member 25, is the horizontally movable, downwardly planar, upwardly curved, sheet-compressing and guiding or guide member 31. The upper curved end 32 of the latter, in one position, extends across the path of the downwardly traveling semi-packet 14, and toward the line or space between rollers 13 and 22, and the planar surfaces of stationary guide plate 26 and of movable guide member 31 are substantially unintcrruptedly coextensive in the plane or" guide plate 26, as shown in FIGS. 6 and 7. As will be apparent, guide member 31 is movable on its pivot 36 to rearward retraction out of the path of said descending semi-packet 14-, to a position in which the planar surfaces of stationary plate 26 and of movable member 31 are angularly divergent, as disclosed in FIG. 7, to permit guided impingement of the semi-packet against stationary guide element 24, and the end of the planar surface of the then sloping guide member 31, and downward entry toward and into the fixed slot 27.

Second cross fold blade means is provided, comprising an arm d9, pivoted at its upper end at 41 to frame 2-3 biased counterclockwise by a spring 79, and pivotally mounting a generally horizontal blade 43 on a pivot The blade is upwardly biased on its pivot 4 by suitable means, to a point at which it just misses intersection with the periphery of crease roll 18, to avoid adverse intersecting contact therewith, whereas, in response to varying thickness of semi-packets it can move away from roll 18 toward roll 22, in a floating relationsmp. Of course as noted roller 22 can float vertically against its bias relative to roll 18 in a manner as disclosed in said application. The arm 4% mounts a framework 5b, the flanges 5i and 52 of which mount a slidable plunger 53 concentric with and engaged by a compression spring 54, with the spring pressed plunger extended toward and in some arm attitudes bearing externally against the pivot d guide plate 31 above its axis 39. A fixed bracket arm 56 is mounted on the stationary plate 2-6 and has its end 5'7 generally juxtaposed to but out of alignment with either flange of the framework 50. A spring 69 extends between end 5'7 of the arm 56 and the movable guide element 31, retracting the latter to the right (in FIG, 5, etc.) against a stop 53 on the arm when no overriding force is efiective on the guide member 31 urging it to the left.

To effect the motions of the creasing blade 43 and of the movable guide member 3-1, in carefully coordinated and controlled synchronism, lever 4a has a cam follower 5 engaging the surface of a cam 81. The latter has three ranges of follower control, to wit the maximum cam rise 82 the intermediate rise 83 and the fall 84. Cyclically operative means are provided effecting one complete rotation of cam 31 functional with any desired timing ele- 5 inent in the system, such as the instantaneous position of a coordinated element, or by photoelectric or like electronic means responsive to the position of any portion of the organization or work, and ultimately by way of a single revolution clutch (not shown but disclosed in said application) With the parts in the position indicated in FIG. 5, the cam 81 is in clockwise rotation with the follower 8% pressed against the cam fall 84, by means of the spring 79, and the lever 40 is so far retracted that the blade 43 thereon is at its maximum retraction. Because of this fact the pressure of the spring pressed plunger 53 has been so withdrawn or diminished that the guide member 31 has retracted under the urge of spring 58 whereby the trap door has been retracted from across the path of the next descending semi-packet. During this interval the descending semi-packet passes across the fay line (the line tangential to both of crease rolls l3 and 22), into the pocket or gap 27.

In due cyclic course, as the advancing crease edge 17 of the semi-packet as merely touched the lower end of the gap 27, if that, the cam 81 continuing in its single rotation causes the high 82 to rise against the follower 89 forcing the lever 43 to the left (in the figures), forcing the blade 43 against the semi-packet id in synchronisrn with tie 'eftward advance of the curved movable guide member 31 to bear against the free end portion of the advancing semi-packet below the blade 43, as shown FIG. 6. Thereby the formation of the second fold, feeding of the crease thereof between crease rolls 1% and 22, is initiated. As the crease rolls establish a tight feeding grip on the thus creased semi-packet, the cam 31 continues to move clockwise so that the high 32 moves from under the follower 4% and the latter moves onto the intermediate carn surface This, of course causes immediate retraction of the blade 43, to a small degree, to clear the path for the upward and guided traverse of the lower portion of the advancing semi-packet below the blade and espeially the free floating terminal flap or tree end portion 2? thereof. The importance of this move will be appreciated when it is recognized that the blade 43 moves to the left toward crease rolls l8 and 22 further than does the upper curved end 32 of the movable guide Ell. it is therefore necessary to withdraw the blade while maint' the attitude of the movable guide member 31. be relatively small withdrawal of the blade 43 to the right, just described, reduces the pressure against guide 31 from the sprin pressed plunger, but to a degree insuflicient to permit the latter to respond to the tension of spring as, so that as shown in FIG. 7, the guide 31 remains in its guiding position while the blade 43 has been retracted to the right to clear the path for the traverse of free floating terminal 29 against the aligned guide surfaces 26 and 3?. toward and between crease rollers 13 and 22. This insures the guided entrance of the lower portion of the semi-packet into and througn the crease rolls l8 and 22, and particularly the controlled guidance of loose flap 29 regardless of its shortness into and between said crease rolls.

With cam 81 in the position shown in PEG. 7 cross folding of the instant sheet is complete and by disengagement of the aforementioned (but not shown) single revolution clutch al cross folding mechanisms, including cam 81 come to rest. Upon completion of the accordion folding of the succeeding sheet to cross folding cycle, and hence, the requisite single revolution of cam 33, is initiated. In due course the follower 8% moves onto cam surface 84, and as shown in FIG. both the blade 43 and the guide member 32 are retracted to the right and the way is clear for the delivery of the said succeeding semi-packet 34 past both of these elements into the slot 27 and the continuation and completion of the second cross fold as just described.

it will be understood that the thickness of the accordion folded sheet forming rudimentary packet 7 depends primarily upon the number of panels formed by the accordion folding, and this depends both upon the setting of the accordion folding apparatus as to widths of panels, and the length of an instant sheet. It will be clear that the blade 43 and guide 31 are retracted from the path of deli cry of the once cross-folded sheet (semi-packet 14), so as to admit same toward the slot or opening 27. This retraction can be cyclic with the entry of cross folding lade 69 between rolls l5 and 16, or with any other signalling device, such as photoelectric signals, as in said application.

While it will be apparent that by suitable organization and as shown, the creasing blade 43 will meet the folded sheet comprising the semi-packet l4, essentially normal to such semi-packet, and having a floating disposition to accord for varying thicknesses of such semi-packet, this is essentially of best utility in forming the second fold in a semi-packet, as, when used with regard to a rudimentary packet it is similar to the creasing organization of said application and involves appreciable relative motion of the rudimentary packet and said blade, involving shock to the apparatus and a small time delay, in forming the first cross fold. However, this is not to say that the form of blade and its mounting in FIG. 5 is not of high utility and efliciency in forming any cross fold, al hough it is primarily preferred for forming a second cross fold.

However, to accelerate cross folding, and especially the first cross fold, it is desired to provide a blade which is aligned with the crease rolls and is simply cocked out of immediate juxtaposition thereto, so as to facilitate the accordion folding of the basic sheet into the rudimentary packet, without interference from the creasing blade, while being quickly positioned across the rudimentary packet in contact therewith for cross-folding. To this end the folding blade organization of FIGS. 1 through 4 is preferred for forming the first cross fold in a rudimentary packet, and which is of equal facility in the forma tion of any subsequent cross fold, when desired.

As particularly shown in FIGS. 3 and 4, an illustrative rudimentary packet '7, formed of panels 11, 1b and 12 (for example), is deposited in generally planar relation on a tray 3 overlying crease rolls l5 and 16. It may also overlie a second pair of crease rolls (not shown), in spaced parallel relation to crease rolls 15 and 16, wherein either pair of crease rolls may be used to provide a cross fold as automatically selected as a function of the width of the instant sheet, as disclosed in said application. For practical purposes the crease rolls l5 and 316, or the second pair of crease rolls, may be considered for association with their own correlated cross folding blade, to be described, for forming the first cross fold in either a sheet of minor width or in a sheet of major width, sheet width hav ng been determined by the distance from the same edge of the instant rudimentary packet.

In any case the rudimentary packet 7 is to be creased in a first cross fold forced into and between crease rolls 15 and 16, from it is delivered either as a com plete packet or as a semi-packet delivered to the second cross folding mechanism which has been explained, depending, for instance as to whether the creasing is from the crease rolls at a minimfl distance from an edge of the rudimentary packet, not shown, or from crease rolls 15 and 16 at a maximum distance from said edge. This requires the operation of a blade or the like aligned with the crease rolls and engaging the upper surface 12 of the illustrative rudimentary packet 7. In order to permit the formulation and deposition of the rudimentary packet 7 on the tray 8, it is required that the creasing blade in its inactive attitude be sufficiently out of the path of the rudirnentary packet during its formation as not to interfere therewith, while being so closely proximate as to avoid the delay formerly encountered in effecting its actuation and with drawal. This invention contemplates means for cocking or angularly withdrawing a blade, cont nuously aligned with the instant crease rolls, and for moving said blade angularly to parallel juxtaposition to the rudimentary 7 packet and then for moving said parallel blade against st id rudimentary packet during said parallelism. This appreciably shortens the time previously required for effecting the first cross fold.

In efiecting this important result a frame member 58' (or two spaced frame members in the usual case) is provided generally normal to the plane of the rudimentary packet 7 and parallel to the axes of crease rolls 15 and 16, in extension. In its face the frame member 53 has a guide groove 61, comprising a linear portion 62, leading and merging into a downwardly curved extension portion 63. A lever 64 is provided, adjacent and parallel to frame member 58, having an arm 59, mounting at its free end a creasing blade 6?), the linear edge of which is generally normal to the lever 64. The lever 64- mounts a laterally projecting stud or roller 65, toward its arm and a laterally projecting stud or roller 66 toward its lower end. The lever 64 as noted is disposed close to the frame member 53, parallel thereto, and the respective rollers 65 and 66 extend into and are guided by the groove 61. The lever 64 has a short, angularly projecting, arm 67, merging into lever as in general line with the inner stud or roller 66 (which latter serves as a movable fulcrum), and the free end of the short arm 67 mounts a cam follower or roller 63. The cam follower 68 bears against the outer periphry of a cam 7d. The latter has rise surfaces 74 and 74 separated by a fall surface 75. The lever 64 has a tension spring or like member 71 urging the lever 64- clockwise (in the figures) about the axis established by the traveling fulcrum roller 66. It also is engaged by a tension or like spring 72 exerting force on the lever generally along the line of the linear portion 62 of the guide groove 61., and generally normal to the line of force of spring 71. The combined forces of the springs 71 and 72 force the follower roller as into continuous contact with the surface of cam 7%. At this point, and during the accordion folding of the sheet into the accordion folded rudimentary packet, as the parts are shown in FIG. 2, the cam 76 is stationary, and the blade 69 is cocked upwardly.

With the parts as shown in FIG. 2, the lever 64 is at an angle to the horizontal and the blade 69 is elevated relative to the horizontal plane of the rudimentary packet 7, although cocked and aligned with the common line of intersection of crease rolls 15 and 16, and therefore is generally out of vertical overlap with rudimentary packet 7 in its horizontal extent, thus permitting the formation of the accordion folds without interference from the creasing blade 69 and contiguous arm 59. If

variation of this clearance is desired the position of the lever 64 can readily be variably predetermined. At any rate, at this juncture, the stud or roller 65 is located in the downwardly curved portion 63 of slot 61, against the tension of spring 71, the stud 66 is located in the linear branch 62 of slot 61, and the roller 68 on arm 67 of the lever is engaged by a high 74 on cam 7%. At this juncture also it will be observed that the lever 64 and blade 69 have attained their maximum outward position, at which the blade 69 is in its maximum cocked spacing from the rudimentary packet 7. Forcing and retaining these several positions is the moment between the roller 68 and the stud 66, with the latter serving as a fulcrum for the lever. When, in due course, automatically upon completion of the rudimentary packet 7, the cross fold phase is initiated, the cam 76* moves, and the roller-follower 68 moves toward low 75, the pressure of the lever arm 67 decreases relative to the fulcrum stud 66 and syn chronously the lever arm 59 begins to respond to the force of spring 71, moving the stud 65 radially in the curved portion 63 of the slot 61, moving the lever about the stud 66 as a fulcrum, advancing the blade 69 toward the rudimentary packet until parallelism of the blade 69* and the rudimentary packet 7, is attained, just before contact therewith is established. As the stud 65 moves in the curved groove extension 63, during the first portion of the movement of follower 68 toward the low 75, the urge of spring '72 is relatively inefiective. However, when the stud 65 emerges from the curved extension 63 into the linear portion 62 of the groove 61 (at which point the blade 69 becomes parallel with the rudimentary packet 7) and as the follower 68 approaches the bottom of low 75, the force of spring 72 becomes effective to pull the lever 64; in the direction of the urge of spring 72, with both rollers or studs 65 and 66 in generally vertical alignment in the linear portion 62 of the slot or groove 61 moving the blade (in its then parallel relation to the rudimentary packet 7 against the said rudimentary packet, and toward and between said crease rolls, forcing a crease therein which is forced into and fed between the crease rolls l5 and i6, and fed therethrough to formation of a semipacket delivered downwardly of the crease rolls 15 and 36. Of course, if the folded sheet being cross folded was a semi-packet already possessing one cross fold the operation would be the same, except for its relative thickness and this is contemplated.

Upon the completion of this creasing operation, at least to the point of engagement of the crease between the crease rolls 15 and 16, which may be very rapid indeed, it is desired to eiiect rapid withdrawal of the blade 69 to its position of retraction. As previously noted, at the completion of the creasing or folding operation the cam follower or roller 68 has moved from the high 74- to the low thereof. With continued rotation of the cam the follower roller 63 begins to ride up on high 74'. This exerts force on the end of the arm 67 and develops a moment about the stud 66, riding in the linear portion of the groove 61. This moves the lever against the tension of spring 72 until such point that the advancing stud 65 enters the curved extensions 63 of the groove, and by force from lever arm 67 about stud 66 as a pivot or fulcrum, passes downwardly into and at least partially through the curved extension 63, against the resistance of the tension spring 71. It will be seen that this forces the lever and thus the blade into the position shown in FIG. 2, at the conclusion of which the blade has been retracted and the loading of springs 71 and 72 is increased, preliminary to the next cycle.

it will be seen that there is a compound motion of the lever 64 mounting the blade 69, the first of which is a turning motion during which the stud 65, in angular motion of the lever, moves along and finally out of the curved portion 63 of the slot 61 into vertical alignment with stud 66, and the second of which is linear of the slot in the linear portion 62 thereof, in the final compressing creasing action of the blade. Normally such compound action would require two separate cams or the like. In the instant invention, by the mechanism disclosed, utilizing the moment between the follower 63 and the pivotal stud 66, and the tensioning devices 71 and 72 both functions are accomplished by a single cam 79. Of course, in reverse the moment forces the lever linearly of the slot to remove the blade from immediate proximity to the rudimentary packet, and then, when stud 65 aligns 'with the curved extension 63' of the slot, forces the stud 65 into and along the slot extension 63 against the force of the increasingly loaded spring '71.

It will be understood that many changes and modifications can be made in the organization as disclosed, Without departing from the spirit of the invention, and that the terms vertical and horizontal are illustrative and not limitative, as any angular or spatial relations may be involved. It will be understood that the blades of FIGS. 1 and 5 may be interchangeably used.

I claim as my invention:

1. Sheet folding apparatus comprising first and second creasing rolls having a common line of substantial intersection, a creasing blade in constant coplanar relation with said common line in a plane passing therethrough, means mounting said creasing blade for angular movement in said plane between a position in which the blade is parallel to the axes of said rolls and a position in which it is angularly displaced relative thereto, and means mounting said blade for movement in said plane in its parallel relation to said axes between a position adjacent to but spaced from said common line and a position closer thereto.

2. Sheet folding apparatus comprising first and second creasing rolls having a common line of mutual intersection, a creasing blade in constant coplanar relation with said common line in a plane passing therethrough, means mounting said creasing blade for angular movement in said plane between a position in which the blade is parallel to the axes of said rolls and a position in which it is angularly displaced relative thereto, and means mounting said blade for movement in said plane in its parallel relation to said axes between a position adjacent to but spaced from said common line and a position closer thereto, in which said creasing blade is mounted on a lever having studs disposed in a guide groove in a stationary member, in which said guide groove comprises both a linear and a curved portion, said lever having an arm, said arm having a follower, a cam against which said follower engages, resilient means effective on said lever, whereby with the studs respectively disposed in the linear and curved portion of the guide groove the blade is retracted, and with both studs in the linear portion the blade is aligned with such sheet on said common line.

3. Sheet folding means comprising means feeding a sheet along a predetermined path, crease rolls having parallel axes in alignment generally parallel to said path,

blade means movable transversely of such sheet forcing a crease therein toward said crease rolls whereby the sheet below the blade reverses its path of movement in feeding between said crease rolls, and guide means having a curved end engaging said sheet below the crease rolls and guiding same therebetween, and means mounting said blade means for movement, a cam follower on said means, a cam having three cam surfaces operative on said follower, said surfaces comprising a high surface forcing said blade to a maximum extension, an intermediate surface permitting said blade means to partially retract, and a low surface permitting said blade to fully retract, said guide means being movable, resilient means connected to said guide means urging it into full retraction, and interconnections between said means mounting and said guide means whereby when actuated by said high shrface the blade means and said guide means move in synchronism against said sheet, and whereby upon said partial retraction of said blade means said guide means remains extended for guiding functions, and upon said full retraction of said blade means said guide means is also fully retracted.

4. Sheet folding apparatus as in claim 2, resilient means engaging said lever, and a cam having a low between two highs, with said follower bearing against said cam, whereby with rotation of said cam the follower moves from a high toward said low and the resilient means moves said lever angularly and when said follower approaches said low the resilient means moves said lever linearly.

5. Sheet folding apparatus for sheets within a range of major widths, each having a cross fold toward one end forming free edges of respectively disparate lengths within said range, comprising a pair of complemental crease rolls, a stationary guide plate forming a substantially planar guide surface and having a substantially linear edge, a movable guide member having a lower generally planar extent merging into an upper curved surface, means mounting the movable guide member on a pivot adjacent to said linear edge whereby in a first position thereof the planar portion of the movable member is substantially uninterruptedly coextensive with the planar guide surface and in another second position thereof the planar end of the surface of the guide member is angularly divergently disposed relative to the said planar guide surface and the upper curved surface is retracted from the crease rolls permitting the infeed of a cross folded sheet between said crease rolls and said stationary guide plate, means moving said movable guide member in synchronism with the outward feed of such cross folded sheet whereby the free end of the cross folded sheet engages the surface comprised of the coextensive surfaces of the guide plate and said movable member to guidance into said crease rolls, and blade means movable transversely of such sheet forcing a crease therein and into said crease rolls.

References Cited in the file of this patent UNITED STATES PATENTS 640,100 Cottrell Dec. 26, 1899 909,841 Adams Jan. 12, 1909 1,535,216 Ehlig Apr. 28, 1925 2,222,076 Kahn Nov. 19, 1940 2,679,393 Abell et a1 May 25, 1954 

1. SHEET FOLDING APPARATUS COMPRISING FIRST AND SECOND CREASING ROLLS HAVING A COMMON LINE OF SUBSTANTIAL INTERSECTION, A CREASING BLADE IN CONSTANT COPLANAR RELATION WITH SAID COMMON LINE IN A PLANE PASSING THERETHROUGH, MEANS MOUNTING SAID CREASING BLADE FOR ANGULAR MOVEMENT IN SAID PLANE BETWEEN A POSITION IN WHICH THE BLADE IS PARALLEL TO THE AXES OF SAID ROLLS AND A POSITION IN WHICH IT IS ANGULARLY DISPLACED RELATIVE THERETO, AND MEANS MOUNTING SAID BLADE FOR MOVEMENT IN SAID PLANE IN ITS PARALLEL RELATION TO SAID AXES BETWEEN A POSITION ADJACENT TO BUT SPACED FROM SAID COMMON LINE AND A POSITION CLOSER THERETO. 